Happy Valley's Siobhan Finneran in new look at thriller with Katherine Kelly

Similarly, we can see Katherine Kelly (Mr Bates vs The Post Office) and Nadine Marshall (Champion) in their roles, with Kelly's character attending a crime scene and talking to an attending officer while Marshall's character is seen looking stressed in a dimly lit room with Finneran.

Described as a "thriller about what happens when the clandestine and morally grey witness protection system breaks down", Protection is inspired by a real-life witness protection officer who served in the Metropolitan Police for 30 years and has also acted as a series consultant.

According to the series synopsis: "Detective Inspector Liz Nyles (Finneran), a single mum juggling a difficult divorce and a sick father, finds herself at the heart of a security breach within her witness protection unit."

The synopsis continues: "Professionally compromised by a secret affair with a colleague, she is determined to uncover the true source of corruption within the police.

"Liz will stop at nothing to redeem herself, the reputation of her lover, and to keep her witnesses and her own family safe. Even if it means breaking all the rules.

"This is the story of a tough but increasingly isolated and under-suspicion police officer as she is pulled into a dangerous conspiracy where nothing is as it seems."

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Additional cast for the series includes Barry Ward (Bad Sisters) and Chaneil Kular (Sex Education), as well as David Hayman (Sid and Nancy), Nichola Burley (The Gold) and Akiya Henry (Silent Witness).

The series was initially announced back in September 2023, and comes from multi-award-winning producer New Pictures, known for its work on The Long Shadow, Des and White House Farm.

Protection has been written by acclaimed screenwriter Kris Mrksa, who commented on the commissioning of the series: "Protection is a suspenseful conspiracy thriller, but it also explores some complex moral questions about how far we should be prepared to go in order to serve the greater good.

"The murky world of witness protection, where hardened criminals are often sheltered in the hope that they will help bring down other criminals, provides the perfect context for examining these thorny issues.

"I'm incredibly excited to be working with the team at New Pictures again in bringing this complex world to life."

Protection is set to premiere on ITV and STV and become available for streaming on ITVX and STV Player this spring.

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